Premature Ventricular Contractions

What are premature ventricular contractions (PVCs)?

Premature ventricular contractions, or PVCs, are a type of abnormal heartbeat. Your heart has 4 chambers: 2 upper atria and 2 lower ventricles. Normally, a special group of cells start the signal to start your heartbeat. These cells are in the sinoatrial (SA) node in the right atrium. The signal quickly travels down your heart’s conducting system. It travels to the left and right ventricle. As it travels, the signal triggers nearby parts of your heart to contract. This allows your heart to squeeze in a coordinated way.

In a premature ventricular contraction, the signal to start your heartbeat comes from one of the ventricles instead. This signal is premature, meaning it happens before the SA node has had a chance to fire. The signal spreads through the rest of your heart, causing a heartbeat. If this happens very soon after the previous heartbeat, your heart will push out very little blood. This causes a feeling of a pause between beats. If it happens a little later, your heart pushes out an almost normal amount of blood. This leads to a feeling of an extra heartbeat. So, the heart has a random “premature” heartbeat sandwiched between many other normal heartbeats.

Occasional PVCs are common in people of all ages, but they are a little more common in older people. They often happen in people without any heart disease. However, PVCs are somewhat more common in people with some kind of heart disease. Only rarely do PVCs cause problems on their own.

What causes PVCs?

Certain things can help set off a premature signal in the ventricles, such as:

Reduced blood flow to your heart

Scarring after a heart attack (myocardial infarction)

Electrolyte abnormalities, like low sodium or potassium levels

Increased adrenaline (such as in anxiety)

Certain drugs, like digoxin

Who is at risk for PVCs?

Many heart conditions increase the risk for PVCs, such as:

Mitral valve prolapse

High blood pressure

Heart attack

Coronary heart disease

Dilated cardiomyopathy

Hypertrophic cardiomyopathy

Congenital heart disease

Heart failure

What are the symptoms of PVCs?

Most people with occasional PVCs do not have symptoms. When symptoms do happen, they are usually minor. Sometimes PVCs cause an unpleasant awareness of the heartbeat (palpitations). Some people may describe feeling a “skipped” or “extra” heartbeat. Dizziness, near-fainting, and a pounding sensation in the neck are other possible symptoms.

Generally, PVCs cause dangerous symptoms only if the person has another heart problem. For example, they might happen in someone whose ventricle already squeezes poorly. So if you have heart failure, you may notice increased symptoms, like shortness of breath. You are also more likely to have symptoms if you have PVCs often.

How are PVCs diagnosed?

Your healthcare provider will ask about your medical history and give you a physical exam. An electrocardiogram (ECG) is the most important test for diagnosis. This test allows your provider to study the signal of your heartbeat for a brief moment in time. Any PVCs during this time will show up on the ECG. In some cases, your healthcare provider might recommend ECG monitoring over a day or two, or up to 30 days. This can help to catch PVCs that don’t happen often.

These may be the only tests your healthcare provider will need. You may need more testing if you have PVCs often, or many in a row. Your provider may look at other causes, including potential heart problems. These tests might include:

Echocardiography, to evaluate heart structure and function

Cardiac stress testing, to see how your heart responds to exercise and to evaluate blood flow through your heart

Blood tests, to check potassium and thyroid levels

How are PVCs treated?

Most people with PVCs do not need any treatment. If are treated for another problem with your heart, your PVCs may decrease. For example, you might take a medicine to lower your blood pressure. This may lower your rate of PVCs.

In some cases, specific treatment may be done to help prevent PVCs. These are used only if you have symptoms from PVCs. Options include:

Beta-blockers

Other medicines to help prevent abnormal heart rhythms

Catheter ablation, to destroy the part of your heart responsible for the abnormal beats

How do I manage PVCs?

Your healthcare provider may give your more instructions about how to manage your PVCs and other medical conditions, such as the following:

Eat a heart-healthy diet

Get enough exercise and maintaining a healthy weight

Avoid too much alcohol and caffeine, which can trigger PVCs

Avoid too much stress and fatigue, which can also trigger PVCs

Get treatment for your other medical conditions, like high blood pressure

Make sure to keep all your medical appointments

When should I call my healthcare provider?

See your healthcare provider right away if you have severe symptoms like chest pain, lightheadedness, or sudden shortness of breath. If your symptoms are getting worse over time, plan to see your healthcare provider soon.

Key points about PVCs

PVCs are a kind of abnormal heart rhythm. The signal to start your heartbeat starts somewhere in the ventricles instead of in the SA node. This can feel like a skipped heartbeat or an extra heartbeat.

PVCs are very common in people of all ages. They are a little more common if you have other heart problems.

Most of the time, PVCs do not cause symptoms. And, most of the time, they do not need treatment.

Medicines and surgical ablation are options if you have PVCs.

Your healthcare provider may want to check you for other heart conditions.